The present classification scheme provides a comprehensive quantitative description of the many possible flow configurations that can occur in single-port, submerged discharges. In our experience, the scheme seems valid for about 95% of practically occurring submerged, single-port discharge situations. The classification methodology--whether as given herein or in the expert-system framework of CORMIX1--appears useful for practical applications in several ways. It provides a guide to the analyst on which predictive models to use. It helps to eliminate design configurations that are undesirable from an engineering or ecological viewpoint. Finally, it serves a pedagogical function by alerting the user to the many different mixing processes that take place in pollutant discharge and to their great sensitivity as conditions vary, often causing changes from one flow pattern to another.